Isodynamic
ISOCLINIC, and ISOearth's surface in three classes of pheare three systems of lines which being from the true meridian. laid down on maps represent the magnomena, the varying intensity of the the needle, and its varying declination force, the varying dip or inclination of ISOGEOTHERMIC LINES, a term infrom the true meridian. troduced by Kupffer for lines drawn on which the mean temperature of the soil is the same.